The present invention relates to a light source apparatus for fluorescence photography, and more particularly to a light source apparatus for fluorescence photography of biomolecule sample gels.
In biotechnology experiments, to all eukaryotes, protein phosphorylation can cause the organism to change the activation of the intracellular protein or enzyme, transmit signal, or regulate cell physiological processes such as cell metabolism, cell growth, cell proliferation or cell cancerization. However, the content of phosphorylated proteins in organism is extremely low and normally kept in a dynamic balance status. It is difficult to detect or analyze the phosphorylated proteins before pre-concentration process.
Western blotting was introduced by Towbin et. al. in 1979 and is now a routine technique for protein analysis. The specificity of the antibody-antigen interaction enables a target protein to be identified in the midst of a complex protein mixture. The biomolecule sample that is separated by gel electrophoresis is labeled with an enzyme or fluorescent dye for qualitative or quantitative analysis.
According to the characteristics of biomolecule samples, different enzymes or fluorescent dyes are used to label the biomolecule samples. After sample labeling, the method for observation is also different. For example, in a DNA fluorescence image observation, a 465 nm blue LED-based backlight is used to excite the labeled DNA sample to fluoresce, and then an optical lens and a CCD camera are used for observation or photographing.
FIG. 1 illustrates fluorescence photographing apparatus in accordance with a prior art. As illustrated, the fluorescence photographing apparatus 10 comprises a photography module 12, an amber filter 141 and a light source module 18.
The light source module 18 comprises a housing 181 having a top opening, a blue filter 187 mounted in the top opening of the housing 181 and a blue LED array 183 disposed in the housing 181 below the top opening. After gel phosphoresis, the DNA gel 16 can be placed on the blue filter 187.
The blue LED array 183 provides a blue light source for exciting the sample. The blue filter 187 allows only blue light with 465 nm wavelength to pass. The DNA in the DNA gel 16 is excited to fluoresce and is able to be observed or photographed by means of the photography module 12.
To enhance the image contrast, an amber filter 141 may be disposed between the photography module 12 and the DNA gel 16 to remove the blue light of the back light source. Further, in order to prevent light spots of the LED light source from interfering in the image, a diffuser is disposed between the blue LED array 183 and the blue filter 187 for diffusing each light spot into a uniform light in a larger area.
The aforesaid fluorescence photography apparatus in accordance with a prior art is workable for fluorescence photographing and observation. However, due to structural limitation, one apparatus is suitable for exciting light source with single wavelength. Furthermore, the diffuser 185 in the light source module 18 will reduce the intensity of the exciting light source and increase the energy consumption.